Hearing doors close we shut it down to see what dad had in mind to finish off the evening. We followed him back to the corral. He took off the blanket, stacked the hay bales one on top of the other, put the blanket on top and turned to mom.
“All right dear, you first.”
Mom went to lie down face up along the stack with her arms hanging down and her bottom just hanging off the end. Her legs were spread wide just touching the ground.
As soon as she did that sis and I looked wide eyed at one another. Surely it couldn’t be what we’d just seen on line? But as dad beckoned sis over we knew it was.
Oh! My! Goodness!
Dad had sis walk right between mom’s legs, bend over her to place her head between mom’s chin and boobs and spread her legs.
“All right son. I can see from your face you found this on line already so, Happy Birthday! Step right up. I’ll expect my turn when we get back from vacation.”
When I stepped up it was to find two well exposed, closely stacked pussies facing me. Wow!
I was about to become an actual mother fucker and somehow that was going to be just fine.
I took the easiest target first and slid right into mom. All the way. “Oh!”, she said in surprise.
It dawned on me neither girl could tell when she was going to be penetrated. Cool. I gave mom a few strokes and started alternating. When I was in sis I tried to make sure the strokes were hard enough to make my balls slap into mom’s opening.
In no time at all sis was sucking mom’s tits and mom was stroking the sides of sis’s boobs while they both moaned in concert with my efforts.
Mom climaxed first with a nice full throat scream. Sis came a dozen hard strokes later and set the chickens to squawking again. I came at that point, inside, outside, and all over both of them in a spectacularly slippery mess of a finish.
I spent a moment slumped over sis while running my hands over both of them.
“Got it!” said dad waving his camera triumphantly.
We all got back to the kitchen though three of us were a little weak in the knees for the first bit of the trip.
Our folks went upstairs to bed and sis and I did something else we’d never done. We took the nice, cozy twin bed in the guest room.
We managed to get through a shared shower without any more sex. I was still deflated. We did get some sleep but not as much as we might have. We simply made slow, steady love every hour or two till dawn.
At some point in the wee hours I asked sis, “Hey honey?”
“Uh huh.”
“I’m keeping you full, any real chance you might get pregnant from all this tonight?”
“Uh huh.”
I waited a bit. “Is ‘Uh huh’ all you’ve got to say?”
“Uh huh.” Then she giggled quietly so I poked her gently in the ribs.
With a small squeal she said, “There’s a fair chance. I’ve been ovulating today after all.”
That caused a thrill of excitement to run through me but all I said was, “That’s fine sis that’s just fine.”
And it was and still is.